Since it is often inconvenient or expensive to transport and store chemical solutions at their intended working concentrations, various methods have been developed to mix concentrated chemicals into a flow stream of other fluids. Water is commonly used as a fluid to transport various chemicals which are intended to be used in a dilution ratio. Metering pumps, batch tanks, and pre-mixing solutions for spraying of concentrated chemicals are all typical methods currently in use today. Feeding chemicals into a system by using a venturi is also common. Because many chemicals are now distributed in a concentrated form the potential for increased wear to components due to corrosive effects of the concentrated chemicals or clogging of higher viscosity fluids as compared to a diluted solution has increased.
Currently in the marketplace, many chemical delivery systems typically also have extensive space requirements. For example, in the typical automated car wash there may be a need for a tank for a pre-mixed solution, multiple pumps, and valves associated with the variety of chemicals, detergents and other rinsing or washing agents. Generally, a “hydrominder” is used, in conjunction with a pump and valves to take a chemical from a tank or reservoir, to mix the chemical with water and deposit the solution in an additional tank before the diluted solution is pumped through a pump, typically air driven and applied through a sprayer. This process, and the associated equipment, may be required for each individual chemical employed by the system. Because most automatic car washes utilize several detergents or other chemicals the process results in a large quantity of tanks, pumps, valves, piping, and a significant space requirement. Representative prior art chemical delivery systems for automated car washes include U.S. Pat. Nos. 5,439,020, 6,113,007 and 6,718,216, each of which is herein incorporated by reference. The operating environment for a typical automated car wash also presents unique challenges to an installed chemical delivery system. Often these car wash systems are located in proximity to a service or fueling station. In certain locations these businesses may only be staffed by a single employee monitoring the station and working behind the counter. As such, an individual is not always available to provide service to the car wash if there are maintenance problems. In addition, it is desirable to employ equipment and components that are resistant to the combined corrosive effects of the chemicals in use due to the relatively small, enclosed spaces and high moisture environment. It is also desirable to reduce the number of components in a system, especially those that are prone to wear, such as pumps and mechanical valves. The combination of a harsh environment and component wear directly contributes to the need to perform service and maintenance on a car was system in order to ensure its operation. Finally, the typical Hydrominder installation is subject to fluctuations in supply water pressure such that dilution ratios can of water to chemical are varied.
Therefore, a need exists for further improvement to chemical delivery system designs that are capable of handling a variety of concentrated chemicals in such a manner as to reduce the amount of service required to maintain the system. The system should be able to accurately and consistently deliver an appropriate quantity of concentrated chemicals with appropriate dilution ratios as needed by the application and to provide an efficient system to dilute the chemicals to their proper strength before being utilized in the system. Additionally, the system should be configured such that it physically occupies as little space as necessary.